using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using DocumentCreationSystem.Models;
using Microsoft.Extensions.Logging;

namespace DocumentCreationSystem.Services
{
    /// <summary>
    /// 智能内容规划服务实现
    /// </summary>
    public class IntelligentContentPlanningService : IIntelligentContentPlanningService
    {
        private readonly ILogger<IntelligentContentPlanningService> _logger;
        private readonly IAIService _aiService;
        private readonly IContentQualityAssessor _qualityAssessor;

        public IntelligentContentPlanningService(
            ILogger<IntelligentContentPlanningService> logger,
            IAIService aiService,
            IContentQualityAssessor qualityAssessor)
        {
            _logger = logger;
            _aiService = aiService;
            _qualityAssessor = qualityAssessor;
        }

        /// <summary>
        /// 生成自适应大纲
        /// </summary>
        public async Task<AdaptiveOutline> GenerateAdaptiveOutlineAsync(
            ContentPlanningRequest request, 
            CancellationToken cancellationToken = default)
        {
            try
            {
                _logger.LogInformation($"开始生成自适应大纲，内容类型: {request.ContentType}");

                // 1. 分析内容需求和复杂度
                var complexity = await AnalyzeContentComplexityAsync(request);
                
                // 2. 选择最佳生成策略
                var strategy = SelectOptimalStrategy(complexity, request);
                
                // 3. 生成基础大纲结构
                var baseOutline = await GenerateBaseOutlineAsync(request, strategy);
                
                // 4. 智能优化大纲结构
                var optimizedOutline = await OptimizeOutlineStructureAsync(baseOutline, request);
                
                // 5. 预测质量并调整
                var qualityPrediction = await PredictContentQualityAsync(
                    new OutlineStructure { Sections = optimizedOutline.Sections.Select(s => s.Title).ToList() });
                
                optimizedOutline.EstimatedQualityScore = qualityPrediction.OverallQualityScore;
                optimizedOutline.Strategy = strategy;
                optimizedOutline.Complexity = complexity;

                _logger.LogInformation($"自适应大纲生成完成，预估质量分数: {qualityPrediction.OverallQualityScore:F2}");
                return optimizedOutline;
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "生成自适应大纲时发生错误");
                throw;
            }
        }

        /// <summary>
        /// 预测内容质量
        /// </summary>
        public async Task<QualityPrediction> PredictContentQualityAsync(
            OutlineStructure outline, 
            CancellationToken cancellationToken = default)
        {
            try
            {
                _logger.LogInformation("开始预测内容质量");

                var prediction = new QualityPrediction();
                
                // 1. 结构质量评估
                var structuralScore = EvaluateStructuralQuality(outline);
                prediction.DimensionScores["Structural"] = structuralScore;
                
                // 2. 逻辑连贯性评估
                var logicalScore = await EvaluateLogicalCoherenceAsync(outline);
                prediction.DimensionScores["Logical"] = logicalScore;
                
                // 3. 内容完整性评估
                var completenessScore = EvaluateContentCompleteness(outline);
                prediction.DimensionScores["Completeness"] = completenessScore;
                
                // 4. 创新性评估
                var innovationScore = await EvaluateInnovationPotentialAsync(outline);
                prediction.DimensionScores["Innovation"] = innovationScore;
                
                // 5. 计算总体质量分数
                prediction.OverallQualityScore = CalculateOverallQualityScore(prediction.DimensionScores);
                
                // 6. 识别潜在问题
                prediction.PotentialIssues = await IdentifyPotentialIssuesAsync(outline, prediction.DimensionScores);
                
                // 7. 生成改进建议
                prediction.ImprovementSuggestions = GenerateQualityImprovementSuggestions(prediction);
                
                // 8. 计算预测置信度
                prediction.Confidence = CalculatePredictionConfidence(prediction);

                _logger.LogInformation($"质量预测完成，总体分数: {prediction.OverallQualityScore:F2}，置信度: {prediction.Confidence:F2}");
                return prediction;
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "预测内容质量时发生错误");
                throw;
            }
        }

        /// <summary>
        /// 优化生成计划
        /// </summary>
        public async Task<OptimizedGenerationPlan> OptimizeGenerationPlanAsync(
            GenerationPlan plan, 
            CancellationToken cancellationToken = default)
        {
            try
            {
                _logger.LogInformation("开始优化生成计划");

                var optimizedPlan = new OptimizedGenerationPlan();
                
                // 1. 分析当前计划的瓶颈
                var bottlenecks = AnalyzePlanBottlenecks(plan);
                
                // 2. 优化执行顺序
                optimizedPlan.Steps = OptimizeExecutionOrder(plan.Steps);
                
                // 3. 优化资源分配
                optimizedPlan.ResourceAllocation = OptimizeResourceAllocation(plan, bottlenecks);
                
                // 4. 计算预估执行时间
                optimizedPlan.EstimatedDuration = CalculateOptimizedDuration(optimizedPlan.Steps);
                
                // 5. 计算优化指标
                optimizedPlan.Metrics = CalculateOptimizationMetrics(plan, optimizedPlan);

                _logger.LogInformation($"生成计划优化完成，预估时间节省: {optimizedPlan.Metrics.TimeSaving:P2}");
                return optimizedPlan;
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "优化生成计划时发生错误");
                throw;
            }
        }

        /// <summary>
        /// 验证全局一致性
        /// </summary>
        public async Task<ConsistencyReport> ValidateGlobalConsistencyAsync(
            DocumentContent content, 
            CancellationToken cancellationToken = default)
        {
            try
            {
                _logger.LogInformation("开始验证全局一致性");

                var report = new ConsistencyReport();
                
                // 1. 术语一致性检查
                report.TerminologyConsistency = await CheckTerminologyConsistencyAsync(content);
                
                // 2. 风格一致性检查
                report.StyleConsistency = await CheckStyleConsistencyAsync(content);
                
                // 3. 逻辑一致性检查
                report.LogicalConsistency = await CheckLogicalConsistencyAsync(content);
                
                // 4. 格式一致性检查
                report.FormatConsistency = CheckFormatConsistency(content);
                
                // 5. 计算总体一致性分数
                report.OverallConsistencyScore = CalculateOverallConsistencyScore(report);
                
                // 6. 收集所有问题
                report.Issues = CollectConsistencyIssues(report);
                
                // 7. 生成修复建议
                report.FixSuggestions = GenerateFixSuggestions(report.Issues);

                _logger.LogInformation($"一致性验证完成，总体分数: {report.OverallConsistencyScore:F2}");
                return report;
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "验证全局一致性时发生错误");
                throw;
            }
        }

        /// <summary>
        /// 智能字数分配
        /// </summary>
        public async Task<WordAllocationPlan> AllocateWordsIntelligentlyAsync(
            AdaptiveOutline outline, 
            int totalWordCount, 
            CancellationToken cancellationToken = default)
        {
            try
            {
                _logger.LogInformation($"开始智能字数分配，总字数: {totalWordCount}");

                var plan = new WordAllocationPlan
                {
                    TotalWordCount = totalWordCount,
                    Allocations = new List<SectionWordAllocation>()
                };

                // 1. 计算各章节的重要性权重
                CalculateImportanceWeights(outline.Sections);
                
                // 2. 基于复杂度调整权重
                AdjustWeightsByComplexity(outline.Sections);
                
                // 3. 分配字数
                var remainingWords = totalWordCount;
                foreach (var section in outline.Sections)
                {
                    var allocation = new SectionWordAllocation
                    {
                        SectionId = section.Id,
                        SectionTitle = section.Title,
                        AllocatedWords = (int)(totalWordCount * section.ImportanceWeight),
                        Weight = section.ImportanceWeight,
                        ComplexityLevel = section.ComplexityLevel
                    };
                    
                    plan.Allocations.Add(allocation);
                    remainingWords -= allocation.AllocatedWords;
                }
                
                // 4. 分配剩余字数
                DistributeRemainingWords(plan.Allocations, remainingWords);
                
                // 5. 验证分配合理性
                ValidateWordAllocation(plan);

                _logger.LogInformation($"智能字数分配完成，分配给 {plan.Allocations.Count} 个章节");
                return plan;
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "智能字数分配时发生错误");
                throw;
            }
        }

        /// <summary>
        /// 生成内容改进建议
        /// </summary>
        public async Task<List<ImprovementSuggestion>> GenerateImprovementSuggestionsAsync(
            string content, 
            QualityMetrics qualityMetrics, 
            CancellationToken cancellationToken = default)
        {
            try
            {
                _logger.LogInformation("开始生成内容改进建议");

                var suggestions = new List<ImprovementSuggestion>();
                
                // 1. 基于质量指标生成建议
                suggestions.AddRange(GenerateQualityBasedSuggestions(qualityMetrics));
                
                // 2. 基于内容分析生成建议
                suggestions.AddRange(await GenerateContentBasedSuggestionsAsync(content));
                
                // 3. 基于最佳实践生成建议
                suggestions.AddRange(GenerateBestPracticeSuggestions(content));
                
                // 4. 排序和优先级设置
                suggestions = suggestions.OrderByDescending(s => s.Priority).ToList();

                _logger.LogInformation($"生成了 {suggestions.Count} 条改进建议");
                return suggestions;
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "生成内容改进建议时发生错误");
                throw;
            }
        }

        #region 私有辅助方法

        private async Task<ComplexityAssessment> AnalyzeContentComplexityAsync(ContentPlanningRequest request)
        {
            // 实现内容复杂度分析逻辑
            var complexity = new ComplexityAssessment();
            
            // 基于内容类型评估基础复杂度
            complexity.ContentComplexity = request.ContentType switch
            {
                "学术论文" => 4,
                "技术文档" => 3,
                "商业报告" => 3,
                "创意写作" => 2,
                _ => 2
            };
            
            // 基于字数评估结构复杂度
            complexity.StructuralComplexity = request.TargetWordCount switch
            {
                > 10000 => 4,
                > 5000 => 3,
                > 2000 => 2,
                _ => 1
            };
            
            // 基于质量要求评估逻辑复杂度
            complexity.LogicalComplexity = request.QualityLevel;
            
            // 计算总体复杂度
            complexity.OverallComplexity = (complexity.ContentComplexity + 
                                          complexity.StructuralComplexity + 
                                          complexity.LogicalComplexity) / 3;
            
            // 预估生成时间
            complexity.EstimatedGenerationTime = complexity.OverallComplexity * request.TargetWordCount / 100;
            
            return complexity;
        }

        private GenerationStrategy SelectOptimalStrategy(ComplexityAssessment complexity, ContentPlanningRequest request)
        {
            var strategy = new GenerationStrategy();

            if (complexity.OverallComplexity >= 4)
            {
                strategy.Name = "高质量迭代策略";
                strategy.Mode = GenerationMode.Sequential;
                strategy.IterationCount = 3;
            }
            else if (complexity.OverallComplexity >= 3)
            {
                strategy.Name = "平衡优化策略";
                strategy.Mode = GenerationMode.Hybrid;
                strategy.IterationCount = 2;
            }
            else
            {
                strategy.Name = "快速生成策略";
                strategy.Mode = GenerationMode.Parallel;
                strategy.IterationCount = 1;
            }

            return strategy;
        }

        private async Task<AdaptiveOutline> GenerateBaseOutlineAsync(ContentPlanningRequest request, GenerationStrategy strategy)
        {
            var outline = new AdaptiveOutline
            {
                Title = request.Topic,
                Strategy = strategy
            };

            // 基于内容类型生成基础章节结构
            var baseSections = request.ContentType switch
            {
                "学术论文" => new[] { "摘要", "引言", "文献综述", "研究方法", "结果分析", "讨论", "结论", "参考文献" },
                "技术文档" => new[] { "概述", "系统架构", "功能说明", "使用指南", "API文档", "故障排除", "附录" },
                "商业报告" => new[] { "执行摘要", "背景介绍", "市场分析", "解决方案", "实施计划", "风险评估", "结论建议" },
                _ => new[] { "引言", "主体内容", "总结" }
            };

            foreach (var sectionTitle in baseSections)
            {
                outline.Sections.Add(new AdaptiveSection
                {
                    Title = sectionTitle,
                    Description = $"{sectionTitle}部分的详细内容",
                    ImportanceWeight = 1.0 / baseSections.Length,
                    ComplexityLevel = 2,
                    Priority = outline.Sections.Count + 1
                });
            }

            return outline;
        }

        private async Task<AdaptiveOutline> OptimizeOutlineStructureAsync(AdaptiveOutline outline, ContentPlanningRequest request)
        {
            // 基于用户要求调整大纲结构
            if (!string.IsNullOrEmpty(request.UserRequirements))
            {
                // 这里可以使用AI分析用户要求并调整大纲
                _logger.LogInformation("根据用户要求优化大纲结构");
            }

            // 调整章节权重
            foreach (var section in outline.Sections)
            {
                if (section.Title.Contains("核心") || section.Title.Contains("主要"))
                {
                    section.ImportanceWeight *= 1.5;
                }
            }

            return outline;
        }

        private double EvaluateStructuralQuality(OutlineStructure outline)
        {
            var score = 70.0; // 基础分数

            // 章节数量合理性
            if (outline.Sections.Count >= 3 && outline.Sections.Count <= 10)
                score += 10;

            // 标题清晰性
            if (outline.Sections.All(s => !string.IsNullOrWhiteSpace(s)))
                score += 10;

            // 逻辑顺序
            score += 10; // 简化评估

            return Math.Min(score, 100);
        }

        private async Task<double> EvaluateLogicalCoherenceAsync(OutlineStructure outline)
        {
            // 简化的逻辑连贯性评估
            return 75.0;
        }

        private double EvaluateContentCompleteness(OutlineStructure outline)
        {
            // 基于章节完整性评估
            return outline.Sections.Count >= 3 ? 80.0 : 60.0;
        }

        private async Task<double> EvaluateInnovationPotentialAsync(OutlineStructure outline)
        {
            // 简化的创新性评估
            return 70.0;
        }

        private double CalculateOverallQualityScore(Dictionary<string, double> dimensionScores)
        {
            return dimensionScores.Values.Average();
        }

        private async Task<List<PotentialIssue>> IdentifyPotentialIssuesAsync(OutlineStructure outline, Dictionary<string, double> scores)
        {
            var issues = new List<PotentialIssue>();

            foreach (var score in scores)
            {
                if (score.Value < 60)
                {
                    issues.Add(new PotentialIssue
                    {
                        Type = score.Key,
                        Description = $"{score.Key}质量较低",
                        Severity = 3,
                        Solution = $"建议改进{score.Key}相关内容"
                    });
                }
            }

            return issues;
        }

        private List<string> GenerateQualityImprovementSuggestions(QualityPrediction prediction)
        {
            var suggestions = new List<string>();

            foreach (var issue in prediction.PotentialIssues)
            {
                suggestions.Add(issue.Solution);
            }

            if (prediction.OverallQualityScore < 70)
            {
                suggestions.Add("建议增加更多细节和深度");
            }

            return suggestions;
        }

        private double CalculatePredictionConfidence(QualityPrediction prediction)
        {
            // 基于评估维度的一致性计算置信度
            var scores = prediction.DimensionScores.Values.ToList();
            var variance = scores.Sum(s => Math.Pow(s - scores.Average(), 2)) / scores.Count;
            return Math.Max(0.5, 1.0 - variance / 1000);
        }

        // 添加其他缺失的方法实现
        private List<string> AnalyzePlanBottlenecks(GenerationPlan plan)
        {
            return new List<string> { "资源限制", "依赖关系" };
        }

        private List<GenerationStep> OptimizeExecutionOrder(List<GenerationStep> steps)
        {
            return steps.OrderBy(s => s.Order).ToList();
        }

        private ResourceAllocation OptimizeResourceAllocation(GenerationPlan plan, List<string> bottlenecks)
        {
            return new ResourceAllocation
            {
                CpuUsage = 0.7,
                MemoryUsage = 1024,
                ConcurrentTasks = 3,
                ModelCalls = plan.Steps.Count * 2
            };
        }

        private TimeSpan CalculateOptimizedDuration(List<GenerationStep> steps)
        {
            return TimeSpan.FromMinutes(steps.Sum(s => s.EstimatedTime.TotalMinutes) * 0.8);
        }

        private OptimizationMetrics CalculateOptimizationMetrics(GenerationPlan original, OptimizedGenerationPlan optimized)
        {
            return new OptimizationMetrics
            {
                EfficiencyImprovement = 0.2,
                QualityImprovement = 0.15,
                TimeSaving = 0.25,
                ResourceUtilization = 0.8
            };
        }

        private async Task<ConsistencyCheck> CheckTerminologyConsistencyAsync(DocumentContent content)
        {
            return new ConsistencyCheck
            {
                Score = 85,
                Status = CheckStatus.Passed,
                Details = "术语使用基本一致",
                IssueCount = 2
            };
        }

        private async Task<ConsistencyCheck> CheckStyleConsistencyAsync(DocumentContent content)
        {
            return new ConsistencyCheck
            {
                Score = 80,
                Status = CheckStatus.Passed,
                Details = "写作风格保持一致",
                IssueCount = 3
            };
        }

        private async Task<ConsistencyCheck> CheckLogicalConsistencyAsync(DocumentContent content)
        {
            return new ConsistencyCheck
            {
                Score = 90,
                Status = CheckStatus.Passed,
                Details = "逻辑结构清晰",
                IssueCount = 1
            };
        }

        private ConsistencyCheck CheckFormatConsistency(DocumentContent content)
        {
            return new ConsistencyCheck
            {
                Score = 95,
                Status = CheckStatus.Passed,
                Details = "格式规范统一",
                IssueCount = 0
            };
        }

        private double CalculateOverallConsistencyScore(ConsistencyReport report)
        {
            var scores = new[]
            {
                report.TerminologyConsistency.Score,
                report.StyleConsistency.Score,
                report.LogicalConsistency.Score,
                report.FormatConsistency.Score
            };
            return scores.Average();
        }

        private List<InconsistencyIssue> CollectConsistencyIssues(ConsistencyReport report)
        {
            var issues = new List<InconsistencyIssue>();

            if (report.TerminologyConsistency.IssueCount > 0)
            {
                issues.Add(new InconsistencyIssue
                {
                    Type = "术语不一致",
                    Description = "发现术语使用不一致的情况",
                    Severity = IssueSeverity.Medium,
                    FixSuggestion = "统一术语使用"
                });
            }

            return issues;
        }

        private List<string> GenerateFixSuggestions(List<InconsistencyIssue> issues)
        {
            return issues.Select(i => i.FixSuggestion).Distinct().ToList();
        }

        private void CalculateImportanceWeights(List<AdaptiveSection> sections)
        {
            foreach (var section in sections)
            {
                section.ImportanceWeight = 1.0 / sections.Count;
            }
        }

        private void AdjustWeightsByComplexity(List<AdaptiveSection> sections)
        {
            foreach (var section in sections)
            {
                section.ImportanceWeight *= (section.ComplexityLevel / 3.0);
            }
        }

        private void DistributeRemainingWords(List<SectionWordAllocation> allocations, int remainingWords)
        {
            if (remainingWords > 0 && allocations.Any())
            {
                var wordsPerSection = remainingWords / allocations.Count;
                foreach (var allocation in allocations)
                {
                    allocation.AllocatedWords += wordsPerSection;
                }
            }
        }

        private void ValidateWordAllocation(WordAllocationPlan plan)
        {
            var totalAllocated = plan.Allocations.Sum(a => a.AllocatedWords);
            if (Math.Abs(totalAllocated - plan.TotalWordCount) > 100)
            {
                _logger.LogWarning($"字数分配偏差较大: 目标{plan.TotalWordCount}, 实际{totalAllocated}");
            }
        }

        private List<ImprovementSuggestion> GenerateQualityBasedSuggestions(QualityMetrics metrics)
        {
            var suggestions = new List<ImprovementSuggestion>();

            if (metrics.LogicalCoherence < 70)
            {
                suggestions.Add(new ImprovementSuggestion
                {
                    Type = SuggestionType.Logic,
                    Title = "改进逻辑连贯性",
                    Description = "内容逻辑关系需要加强",
                    Priority = 4
                });
            }

            return suggestions;
        }

        private async Task<List<ImprovementSuggestion>> GenerateContentBasedSuggestionsAsync(string content)
        {
            var suggestions = new List<ImprovementSuggestion>();

            if (content.Length < 1000)
            {
                suggestions.Add(new ImprovementSuggestion
                {
                    Type = SuggestionType.Content,
                    Title = "增加内容深度",
                    Description = "内容篇幅较短，建议增加更多细节",
                    Priority = 3
                });
            }

            return suggestions;
        }

        private List<ImprovementSuggestion> GenerateBestPracticeSuggestions(string content)
        {
            var suggestions = new List<ImprovementSuggestion>();

            if (!content.Contains("总结") && !content.Contains("结论"))
            {
                suggestions.Add(new ImprovementSuggestion
                {
                    Type = SuggestionType.Structure,
                    Title = "添加总结部分",
                    Description = "建议在文档末尾添加总结或结论",
                    Priority = 2
                });
            }

            return suggestions;
        }

        #endregion
    }
}
